Improvement in sewing-machines



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A. TITTMAN.

$ewing Machine.

Patented April 20, 1869.

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A. TITTMAN.

Sewing Machine. No.- 89,093. Patnted April 20, 1869.-

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ALEXANDER TIT'IMAN, OF INDIANAPOLIS, INDIANA,ASSIGNOR HIMSELFWILLIAM H. TURNER, AND DUNCAN HENDERSON.

Letters Patent No. 89,093, dated April 20, 1869.

IMPROVEMENT IN SEWING-MACHINES.

To all whom it may concern:

Be it known that I, ALEXANDER TITTMAN, of Indianapolis, in the county of Marion, and State of Indiana, have invented certain new and useful Improvements in Sewing-Machines; and I do hereby declare.

that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, making apart of this specification, in which- Figure 1 is a vertical longitudinal section of my machine, arranged with two threads for making the double loop stitch or double-lock stitch, fiuniliarly known as the Grover and Baker stitch.

Figure 2 is a longitudinal section through the machine, showing the arrangement for making it shuttle or single-loop stitch.

. Figure 3 is atransversc section through the bedplate of the machine, showing a front view of the parts arranged as in 1.

Figure 4 is a rear end View of the parts beneath the bed-plate of the machine.

Figure 5, is a sectional view in detail of my improved mode of holding and adjusting the metallic bobbin which carries the lower thread in the arrange.- ment of fig. 2.

Figure 6 is a view in detail of my improved spring tension device for the lower thread which is used in connection with the devices for making the double-loop stitch.

Figure 7 shows the looper and needle for making a double-loop stitch.

Figure 8 shows the needle and hook for making the lock or shuttle-stitch.

Similar letters of reference indicate corresponding parts in the several figures.

The object of my invention and improvement in sewing-machines is to adapt a machine to make, with two threads, the double-loop. stitch or the lockstitch, whichever may be desired, without detaching from the machine any of its parts, or applying other parts thereto to efi'ect the conversion, as'will be hereinafter described.

To enable others skilled in the art to make and use my invention, I will describe its construction and operation.

The bed-plate A is constructed with an opening through it below and in front of the upper needle, which opening is covered by the plates B D, that can be removed for obtaining access to the looper E, which is arranged beneath and near these plates B I).

At the opposite end of the bed-plate A, and cast with this plate, is a box which forms a receptacle for the shaft 7) of the needle-carrying arm G, which vibrates on the centres c c by means of the lever F, having a slot, (1, in its end for the reception of a pin attached to the crank-plate e on shaft 0, and driven by the pulley \V.

The tension disks V are held in position by the stud K, which is screwed to the necdle-arm G, and receives the thread from the spool placed on the stud which is attached to the pressure-arm H.

In a plane with the needle-arm Gr, cast solid with the shaft 1), and therefore subject to the motionof the same, is the arm I, extending below the bed-plate, which arm carries on its lower end the wrist-pin i for the two connecting rods K L.

The connecting rod K may, at the will of the operator, be disconnected from the wristi by drawing back the spring-bolt M, and suspending this rod K on the hook N, which, at the same time, brings the loopingbar 0, which is hinged to said rod K, back to the farthest possible point, out of the way of the needle and revolving hook.

The other connecting rod L is attached .at one end to the wrist i of arm I, while its opposite end is countersunk to receive either one or the other of the conical nnts'X Y, which, when loosened, will quickly release this connecting rod Ifby the slot L, and allow the hook on arm 1. 2 to be brought into operation for the purpose of adapting the machine for making the lock-stitch as represented in fig. 2.

By means of the motion of arm I, and that of the crank m on the shaft 0, I obtain a motion of the hook on arm N which is well adapted to form the loop of the upper thread, bring it over the bobbin-holder r, and deliver it when this is accomplished.

The double-crank arm N is a short bar, having ahook, 2, on one end, formed, as shown in figs. 2 and 8. This arm is pivoted at or near the middle of its length to the end of crank in, as clearly shown in fig. 4, so that it will partake of the movements of this crank and the arm I.

If the double-loop stitch is desired, the operator releases the nut from the connecting rod L, turns down the hook 2, and attaches this rod by the nut x nearest the hook, thus throwing the hook out of operative action.

The other connecting rod K is then released from book N and brought into connection with the wrist i on arm I, and the forward and backward movement of the looper E is resumed.

To .form this double-loop stitch, it is required that the looper should catch the loop of the upper thread on the same side of the needle as the revolving hook 2 docswhen the latter is used to make the lockstitch. This is done in the forward motion of the looper as the needle ascends, then the looper moves on the opposite side of the needle, and takes its backward stroke. By the increased bulk, observed beupper thread is drawn back out of the way of the needle, and in this position the lower thread is stretched from the next finished stitch to the eye in the point of tween the eyes of the looper, fig. 7, the loop of the,

the looper. The needle passes through the triangle thus formed, and the lower thread is looped round the needle to accomplish the next stitch. The looper now finishes its backward stroke, and returns on the other side of the needle.

The lateral motion of the looper-bar 0, which is held to the bed-plate A by a screw, '20, in a slot at the rear end of this bar, is obtained by a roller which moves in the cam-slot S.

This roller turns on a pin which is formed on the adjustable slotted-plate t, which latter is secured to the looper-slide t by screws, as shown in fig. 4, passing through the plate t.

By loosening the screws which affix plate t to the looper-slide, the looper can be adjusted and set so as to move nearer to or further from the needle in order to catch the loop in a proper manner.

The feed of the machine is worked by the cam T, atiixed to or cast with the shaft of pulley W.

The feed-carrier Z fits into a recess formed in the hangers P, and is held therein by the screw-pin p, and pressed against the working surface of the cam T by the spring a.

In fig. 6 I have represented a top view of a device for applying the requisite degree of tension to the lower thread when the looper is used in making the double-loop stitch.

It will be seen that the spring b by being hinged at x, and fastened forward of this hinge to the rod of the spiral spring m, acts as a lever under a condition hereafter stated, and while thus acting, this spring, by its own elasticity, presses directly with a flexible action upon the pivoted block y, and in the event of an unusual obstruction on the thread, and a consequently unusual strain coining upon the tension contrivance so as to render liablethc breaking of the thread, this lever spring will of itself yield sufliciently to allow the knot or obstruction to pass over the block y. The spring I) is quite thin and delicate, and is curved or bowed,- as shown, so as to conform to the shape of the support of the block y, and also to act'as a guide to the lower thread, this bow allowing the thread to pass incliningly through the tension contrivance without contact with any parts but the block and that portion of the spring I) which bears on the block as represented.

The lower thread passes from a spool on the wire a through a hole in the spring I), which moves on the hinge a, and leaves the same at 11 through another hole. This spring I) presses the thread between it and the pivoted swinging-block y.

The pressure upon the thread is increased or diminished by screwing up or unscrewing the nut n acting on the end of spring on.

By loosening the-nut the spring will act with less force upon the elastic-arm b, and by screwing up the nut the force of the spring will be increased.

From'the above description it will be seen that I am enabled to make a double-loop stitch, familiarly known as the Grover and Baker stitch, by attaching the rear end of rod K to the wrist-pin & on the vibrating-arm I, and changing the connection of the forward end of rod L with crank-arm N from y to 2:, as shown in figs. 1 and 3, thus bringing the looper E into operation with the needle 0n arm G.

To make a lock-stitch the rear end of arm K is detached from I, drawn back and attached to the hook N, as shown in fig. 2. j

This moves the looper back and out of the way of the revolving-hook 2, which latter is brought into operation by attaching the forward end of the connecting rod L to the wrist-pin y, as shown in fig. 2.

The metallic-bobbin r, over-which the hook 2 on the double-crank arnl N carries the loop in forming the. lock-stitch, is clamped between plate's J 0', fig. 5, in such manner as to allow the thread to pass between the outside surfaces of this bobbin and the inside surfaces of the jaws;

The jaw O is rigidly secured to the hanger P, figs. 1, 2, and 5, and the jaw J is formed with a right-angular slotted portion J on it, which receives the feather, or tenon v, projecting from P.

When the jaw J isadjustcd in place on the hanger P, the thumb-screw V is used to secure this jaw rigidly in place.

The slot in the portion J of J is somewhat longer than the feather c, and hence the space between the two jaws J O can be increased or diminished at pleasure according to the size of the thread of the upper needle. The tenon or feather and slot connection serves as a guide to keep the inside surfaces of the plates or jaws J (1' always in planes parallel to each other, however careless a person may be in adjusting the jaw J.

The device which is applied to the rear end of the connecting rod of the looper for facilitating the attachment of this rod to the wrist-pin t on arm 1, consists of a latch-bolt, M, which is acted upon by a spring applied to the bolt in any suitable manner, which bolt closes, when released, the lower end of the slotted opening that receives the wrist-pin 6.

By drawing back the handle formed on bolt M the slot will receive the wrist-pin t, and when released this bolt prevents the rod K from becoming detached from the wrist-pin.

It will be seen that my object is to carry out my invention by a single organization, or by a machine from which it is not necessary to detach or take away any of its parts to effect the change of stitches.

My invention combines within itself all the elements required for making the two stitches above named, and each part is made to assist another part as far as pos sible in both operations.

The driving-wheel \V transmits motion to the needle-bar G, hooked-arm N and looper E through the medium of a single shaft, 7), and rods F K L, no toothed gearing being employed about the machine,

and no interposition of cams between the shaft 7), and. stitch-forming devices other than what are employed upon the main-shaft 0 beneath forward end of the machine.

What I claim as new, and desire to secure by Letters Patent, is

1. So constructing a sewing-machine that it may be made to sew with two threads, forming either a shuttle or lock-stitch, or a double-loop stitch, at the pleasure of the operator, without taking from it any of its parts or adding to it other parts, substantially as described. I

2. A sewing-machine for making the different stitches herein described, wherein are employed a circular bobbin, a turning hook, and a lower-thread-carrying looper, the said elements being permanent fixtures to the machine at all times, substantially as and for the purpose described.

the upper needle or 3. Providing for turning the hook 2 on arm N' out I of the way of the looper, substantially as described, in order to admit of making a double-looped stitch.

4. The connecting rod K, or its equivalent, for put ting the looper out of motion and out of the way of the revolving hook, substantially as described.

5. The application of a latch-bolt, M, .or its equivalent, to the connecting rod K of the looper, substantially as and for the purpose described.

6. The self-acting tension device, shown infig. 6, consisting of a perforated lever spring, I), and pivoted block 1', combined with the devices m a, and operating substantially as described.

' 7. The double-crank arm N 2 provided witha hook,

2, or its equivalent, on one end, and also means for attaching a connecting rod to either end, substantially as and for the purposes described.

8. The organization of a sewing-machine for making the difi'erent stitches herein described, in such manner that both systems of mechanism provided for making thesestitches are operated from the same driving shaft without altering the cam which operates these devices for making both stitches, or the prime motors of the machine, the parts composing the machine being permanent attachments at all times, substantially as and for the purposes set forth.

9. Operating a hook which turns on an axis, and a vibrating or reciprocating thread-cairying looper in one and the same machine, but at difierent times, acc0rd ingly as one or the other of the aforementioned stitches is being formed from the same driving shaft, these ALEXANDER TITTMAN. [SEAL] Witnesses WILLIAM B. FIsHBAGK, A. HUNTINGTON. 

